The present invention pertains to apparatus for sifting out solid particles contained in a gaseous or liquid fluid, having fan or pumping fluid impeller means for causing the fluid to flow through a filter which collects particles larger than the filter aperture size while allowing smaller particles to pass with the fluid out of the apparatus. In this application the word “particle” shall mean any fragment of a solid substance, of whatever size, contained in the gaseous or liquid fluid, so as to be siftable out from the fluid by such apparatus if the particle is larger than the filter aperture size.
There are numerous and quite varied possible applications for such sifting apparatus, as further discussed below, including, for example, cleaning of particle contaminants from air or other gases; cleaning beach sand by sifting out broken glass or other debris which could harm the feet of bathers or detract from the appearance of the beach; extraction of valuable mineral particles contained in a water slurry; collection of soil samples which could be picked up by an air stream; lawn maintenance collection of weeds, leaves and burrs; radiation hazard removal operations, such as removal of a plutonium fragment or dust spill at a nuclear facility; biohazard removal operations, such as removal of spilled anthrax particles; an alternative to auger type transport of food particles in food processing operations; and undersea collection of coins or other small treasure items found around a shipwreck.
The present invention may in various embodiments be useful for any such applications, among others, and employs an approach, detailed below, which synergistically combines two distinct physical means for sifting particles from a fluid.